Thanks for sharing that.
I mainly work late shifts (8hr) for similar reasons. Any early shifts (0430 alarm) and I de-compensate in various, but predictable and consistent phases, during this. There's severe headaches (irrespective if having slept 2hrs or 8hrs), low-period w/out concentration, then a manic phase lol. Afterwards hyper-vigilance is key when driving home in peak hour. Forget the argument "hey, but you've still got the entire day free"! Nope..couching in a tired delirious state till the evening until the body reboots and becomes less "out-of-order".
Nightshift 2100-0600- What can I say! Used to be able to do 7-10 in a row once rhythm (anti-social) set in. But I'd have to wake as close to leaving for work as possible. As I got older, it became harder and harder to readjust into days, took longer and effectively negated the free days. Now I just do a couple per month. I mean, you're constantly fighting your endocrine system with this as cortisol floods your body in the mornings, no matter what the shift. So unhealthy. Ahh..the zombie dead time between 0230-0430